Thoughts on SHTF Communications, by Carl L.

The scope of this article: I was involved in a discussion in the SHTF411 chat-room regarding SHTF radio communications.  Being a licensed Amateur Radio (ham) operator, I jumped in and put my two cents into the mix.  In the course of that discussion, I was asked to write something up on the subject.  

Now, I am no expert on the subject and to be sure.  I sometimes feel that I am the least qualified among my peers.  With that in mind, please understand that much of what I’ve written in this essay is only my opinion and there will be many other more qualified opinions out there.  As such, rebuttal and corrections are welcome.  We all have many things to learn, and I am no exception.   A bit about me: I have been an Amateur Radio operator for about 15 years now.  

I am a no-code technician class, which enables me the use of bottom tier Amateur Radio privileges.  That means that I don’t engage in long distance ham communications over HF frequencies.  I can, however, use any frequencies assigned to the amateur bands, 6 meters (about 54 Megahertz) and above.  My interest in Amateur Radio was formed back in college because my advisor was an avid ham guy.  But I have no real interest in progressing further within the Amateur Radio hobby because my primary purpose for becoming involved in ham radio was that it gave me another outlet to apply my knowledge in electronics.  There is plenty of opportunity for improving my electronics and radio skills at 6-meters and above.  In fact, the real motivator was to provide communications between my wife and I because we couldn’t afford cell phones back in those days, and getting our ham licensees has served us well, from that point of view.   I have been an active participant in the field of electronics ever since I can remember – even at the age of about 5 or 6 years old.  I have a degree in Electronics Technology.  I chose the technology route, rather then a full engineering degree because a technology degree is aimed more at hands-on knowledge, rather then strictly theoretical.  I love working out on the manufacturing floor and felt that sitting at a desk would drive me even more Everyone then calls me loony, but without the mental stress of being cooped up in a four-walled cubical.  

General comments: The conversation in the chat room started out with some of the more mundane technical aspects of radio communications, such as what type radio to use, etc…  But in reality, before you run out and buy some radios, it would be wise to understand what is really out there, and the benefits, as well as the detractions associated with the huge variety of radio equipment that is available.   Let’s start with my views on CB radio, first.   I first got started with CB when I was about sixteen years old.  My first CB radio was an old Johnson Communications CB radio that used vacuum tubes.  It was a good radio and I got many years use out of the thing.  They were quite forgiving.  In fact, I used the metal springs of my bed as an antenna.  If you tried that with a modern day radio, the RF finals would blow out in a matter of a second or two.   From my point of view, the CB (about 27 to 28 Megahertz) is too public for use in a SHTF scenario.  Plus, the typical inexpensive CB radio only has 40 channels, while the better radios also have upper and lower side-band.  While CB would be better then nothing, I think the construction of hand-held CB radios is sub-standard and they are bulky.  I would stay away from CB, if at all possible.  

Then there is the Family Radio Service (FRS).  As the name implies, this radio service was intended to be used for family activities, such as camping, hiking, bicycle riding, boating, hunting and other general purpose family communications activities.  The advantage of FRS over CB is that, while CB uses Amplitude Modulation (AM), and is very interference prone while, FRS uses Frequency Modulation (FM), is relatively noise free.  A considerable disadvantage to FRS might be that, it operates on a much higher frequency and therefore its operation is typically only good for “Line-Of-Sight” communications.  Bear in mind that, if you can’t see the other radio, you can’t communicate with that other radio.  Basically, if there are hills or buildings between you and the other individual you are trying to communicate with, quality and reliability of the communications will be severely degraded.   CB, on the other hand, is more dependent on atmosphere conditions.  We have all heard of the term “Skip”.  Skip occurs when the atmosphere is in such a condition that radio waves traveling up into the atmosphere can be reflected back to earth, extending the effective range of communications.  But this mode of communications isn’t reliable, as the atmosphere is continually changing.  You may communicate well today, or even next week, but in a month or so, you might not be able to get past “Line-Of-Sight”.   If you want to communicate by radio in the present scenario and do not want to take the time study for an FCC issued Amateur radio license, CB and FRS are probably your best and cheapest alternatives.  And what ever your personal preference is, as well, is perfectly acceptable.  

If you catch a hint that I might be biased toward Amateur radio and the 2-meter band in particular, it’s because I am!  But to be sure, there are sound reasons that I’m biased toward the 2-meter (144-148 MHz) FM band – based on my particular experience in the 2-meter FM band.  I’m biased heavily toward 2-meter FM because I am already heavily invested in the 2-meter Amateur band.  I’d upgrade to a General or advanced license, for sure.  But the expense I’d have to lay out for good HF (High Frequency, or shortwave) equipment is daunting and I’d much rather spend what money I have available on other survival items. Time is short and I want “The biggest bang for my buck!”  I am in this position, mostly because the 2-meter band offered the best alternative to my wife and me when we first got into Amateur radio.  Back then (and even still today) there were (and still are) an abundance of 2-meter repeaters.  Basically, a repeater listens on one frequency and retransmits on another frequency.  The person doing the talking is listening on the frequency that the repeater transmits on, and transmits on the frequency that the repeater is listening on.  If the repeater antenna is placed on a water tower, hill top or mountain top, communications distances can be increased to a hundred miles or more.  In the area where I live, there are about 80 or so repeaters for use.  There are repeaters that allow a person to talk nation wide.  And there are repeaters that connect to the internet and allow world-wide communications.  But for the latter, you need a web-capable radio to accomplish this amazing feat.  The Yaesu FT-250R hand-held radio has these features available within it, allowing it to communicate over the internet to other repeaters incorporating the web-net feature.  

My Radio Equipment:
Currently, I’ve got mostly a hodgepodge accumulation of 2-meter radios.  My mobile units consist of a 50 Watt Yaesu 8900, a 50 Watt Yaesu 2600, a 50 Watt Kenwood and a 25 Watt Alnico packet-only radio.   For hand-held radios I have a 5 Watt Alnico, a Yaesu 5 Watt 50RD, a Yaesu 5 Watt Vx, a Yaesu 5 Watt FT-150R, two Yaesu 5 Watt FT-250R’s and some off-brand thingy I can’t recall by who.  In addition, I have a 35 Watt linear amplifier in the event that a hand-held unit requires more RF power and I have a 160 Watt linear RF amplifier for the mobile/base units.  Note too, every radio I have will operate from 12VDC, making them all prime for emergency operation from any usable car battery.  So, in combination with my solar power system, reliable communications is a virtual guarantee.  If grid power is available, I have a 50 ampere, 13.8 VDC bench-top power supply that will power the 160 Watt linear amplifier and a couple mobile/base radios.  In addition, I have grid powered and solar powered NiMH battery chargers to ensure longevity of operation of all of the hand-held radios.  The only dud in the bunch of hand-held radios I currently have is the is the Yaesu 50RD.  And that is only because I don’t have a battery pack that will hold NiMH AA batteries so, it’s life is limited to the two factory made NiMH battery pack that I have.   My goal is to eventually have a compliment of hand-held radios that are all the exact same make and model.  There are several benefits to this.  One is that I can purchase software that will enable me to program all of them, the exact same way, standardizing on frequency/memory assignments.  Another advantage is that, even though I have mostly Yaesu hand-held radios, they all operate slightly differently, depending on the specific features within them.  With using all the same model radios, members of the retreat group will only need to become familiar with one radio.  And yet another advantage to employing identical radios is that, as radio parts break or fail, they will all use the same parts.  So, battery packs and antennas – the most likely parts to fail – will all be interchangeable.  

I mentioned Digital Packet.  I don’t really know how viable Digital Packet will be in a SHTF scenario.  I certainly wouldn’t want my call sign being continually broadcast 24/7.  But as I expect there will be emergency traffic on Digital Packet, I’ll probably turn off the transmit feature and simply monitor emergency text messages.  One of the major disadvantages with Digital Packet is that it requires a computer to read the text messages.  In a grid-down scenario, this would not be practical as, I’d want that kind of power being used for other more important uses.   Technical Aspects of radio: A thorough coverage of radio is not practical here, but I will attempt to cover some of the every basics.   From a lay person point of view, there are really only a few terms to know.  

The most talked about seems to be Standing Wave Ratio (SWR).  SWR is basically the amount of RF energy that doesn’t make it out of your antenna and is reflected back into your radio.   SWR is a ratio of RF leaving the antenna (out into space) to the RF being reflected back to the transmitter. High SWR values will destroy the output final of your transmitter.  The cause of high SWR is a result of property mismatches between the transmitter output, the transmission cable and the antenna.  The transmitter is inherently designed to match the transmission cable, providing the proper type cable is used.  The main source of high SWR is a result of property mismatches between the transmission cable and the antenna.  While not all of the antenna mismatching is due to improper antenna length, in large part, an antenna can be tuned to lower the SWR of the transmission system by tuning the antenna length.  The ideal SWR is 1:1.1.  This is considered to be a perfect match.   The device that measures the SWR of your transmission system is called an SWR meter.  Most SWR meters are specifically designed for a specific band of operating frequencies.  That is, you can’t generally use the same SWR meter to tune a 2- meter antenna system and a CB or 10-meter HF transmission system, unless specifically designed to do so.  For CB and 10-meter tuning you will need an HF SWR meter and for 2-meters, you will need a VHF/UHF (Very-High/Ultra-High) frequency SWR meter.   Many CB enthusiasts believe that more power equals more distance.  But is simply a myth!  True, for a given antenna setup, more power will give more distance.  But the chances are, a well-tuned antenna will provide greater effective radiated power (the RF power actually leaving your antenna) then would purchasing a linear RF amplifier.  The mode of thinking should be, perfect your antenna first!  Then, if more Effective Radiated Power (ERP) is required – only after getting the best performance out of your antenna – add the linear RF amplifier.  If the Antenna is not performing at its best, you are only wasting money, power and you are more then likely damaging your transmitter, over the long-haul.  If you already own the SWR meter, or if you can borrow one, best transmitter performance is free, save the time spent.  But to spend a few hundred dollars on a 160 Watt RF linear amplifier would be a total waste, if your antenna was the real problem.   In radio communications, RF power isn’t what the linear RF amplifier uses.  RF power is that which leaves the antenna to do useful transmission of the desired information.  So then, I own a 160 watt linear RF amplifier.  If the amplifier is outputting 160 watts, the RF energy being reflected back to the transmitter is 40 watts, negating transmission line losses, I’m only putting 120 Watts of Effective Radiated Power out of the antenna.  This is about an SWR of 1:1.4, which roughly means about 25% or that precious RF power is being wasted as heat at the RF output of my expensive $360 linear RF amplifier.  In terms of effective radiated power, this is a huge loss.  

There are many, many kinds of antennas.  The two most popular are the “Mono-Pole Ground Plane” and the “Yagi”.  The mono-pole ground plane antenna is Omni-directional – meaning that, the RF energy is transmitted in all directions around a 360 degree circle away from the antenna.  A Yagi antenna is directional.  That is, if you point the Yagi antenna in a specific direction, the bulk of the energy emitted from it will be concentrated in only one direction.  If you think about this, with a ground plane type antenna, the RF energy is sent in all directions and this means that there is less energy traveling in any given direction.  The result is shortened distance, but you effectively are able to communicate equally well in all directions, be it for better or for worse.   But with a Yagi antenna, most of the RF energy is directed toward one direction.  What this means is that you will be able to communicate further in the direction in which the antenna is pointing then you could out of the sides and in the back end of the Yagi antenna.  And please note that, because a Yagi is highly directional, this property dictates that some method will be required to rotate the Yagi (directionally) toward those you intend to communicate with.   Each type of antenna has its purpose.  For me, communication on simplex (without the aid of a repeater, or attempting to reach a repeater at a far distance) a Yagi would be best.  But for local two-way (simplex) communications between my wife and me (especially with hopes of maximum privacy) a mono-pole ground plane antenna would be more effective.   Effective communications tactics in a SHTF scenario: In this area I am very inexperienced. 

I know some of the standard Amateur Radio emergency procedures, but a SHTF scenario like what we all are expecting would require communications methods far different than that for emergency communications.  For one thing, Amateur Radio emergency radios communications are set up to make contact in the broadest of ways.  An emergency ham command post would be attempting to communicate with as many services as possible.   But in a SHTF scenario, I’d tend to think that we would want communications with only those within your retreat group or possible adjacent groups that we may have built a common relationship and trust.  As such, all of the radios in the group would necessarily be required to use the minimum ERP possible.  That means the Command & Control center would probably be operating the mobile/base units at the 5 Watt setting and not the 25 or 50 Watt setting.  Likewise, the remote hand-held devices would necessarily be operating on the 0.5 or 1 Watt setting.  For communications at greater distances, I’d insist that the radio be switched over from the monopole ground plane antenna to the Yagi, and at the lowest power setting that provided reliable communications.  Remember, the Yagi is directional in nature, so all of the energy from the other 280 or so degrees will be concentrated into the remaining 80 degrees, extending communications to a proportionally further distance.   Each member in the group should be well trained on the communications methods that have been established based on some standard of best practices – but those best practices must be decided by the group as a whole, based on your particular situation, or by someone with tactical communications experience.  And that wouldn’t necessarily be me…  

I’d make every individual in the group take on a handle – even the little ones.  That would be some label that will positively identify you within the group, but not to outsiders who might be listening in stealth.   If more then one mobile/base radio is available, use one radio for say, long distance communications or perimeter patrols, and the second unit for internal communications between different activities, such as gardening, medical, mechanical, etc…   Other forms of communications: One form of communications that I believe will be invaluable will be shortwave radio.  While this is mainly a one-way communications method, it will probably provide information from hams, as well as important international information.  Of note, When Iraq invaded Kuwait , I heard some of the first international broadcasts of that event – long before the event was revealed to the U.S. public by the MSM.  In fact, it was so shocking my wife didn’t believe me when I first told her about the invasion.  She thought I was listening to some foreign propaganda.  My wife took the invasion of Kuwait by Iraq more seriously when she was told that she was being deployed to Saudi Arabia, where she then spent the next nine months as a “Desert Rat.”  

If/when you do purchase a shortwave radio, don’t get cheap!  Get a Grundig or comparable quality shortwave radio.  I have two Grundig shortwave radios with a Radio Shack label.  The older shortwave radio is more then 23 years old.  It still works perfectly.  And I’m so confident in this radio, I use it as an alarm clock to wake me every day to go to work.  The newer short wave radio is currently Electromagnetic Pulse (EMP) protected [by storing it is a Faraday enclosure].  It is every bit as good quality as the older radio, but about two thirds the size.  I spent somewhere between $200 and $250 for each of these short wave radios.  They were one of the best purchases I’ve ever made and I wouldn’t hesitate to do it again.   Another device that might be of importance is a general purpose scanner.  While I’ve had one or two scanners over the years, they aren’t something I’ve spent a lot of time getting to know.  But to be sure, if you do decide to purchase a scanner, don’t hesitate to spend the money on a good quality unit – it will repay you many times over.  


Some Useful Links to Amateur Radio Information:

Where it all begins, The ARRL

Testing Preparation

Further Study

Basic radio

More learning

Places to buy gear

Shortwave tutorial

Shortwave Listening